Easily removable multi-paneled locking cover

ABSTRACT

A container cover for use with a container having a neck. The cover includes a lid, a skirt extending downward from the circumference of the lid, and a concentric plug seal extending from the lid inside the skirt. The cover also may include vent holes in the lid. The skirt preferably includes six lock panels. The sides of the lock panels are defined by vertical slots in the skirt, and each lock panel features at least one inwardly-projecting lock. When the cover is locked on the container, the locks engage a lip on the container neck. When a user wishes to remove the cover, the user pulls up on the edge of a lock panel, disengaging the locks from the container lip and removing the cover.

RELATED APPLICATION

This application is continuation-in-part of U.S. patent application Ser.No. 11/654,322, filed on Jan. 17, 2007 and is a continuation in part ofU.S. patent application Ser. No. 11/542,547, filed on Oct. 3, 2006,which are both incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates generally to removable covers forcontainers, and more particularly, to removable and reusable covers foruse with microwavable containers.

BACKGROUND OF THE INVENTION

It is known to provide a removable cover for a container, such as acontainer of food or drink. Many such containers can be placed in amicrowave oven to heat their contents. The cover or closure functions toprevent the contents of the container from spilling when the containeris moved, or splattering when being heated in the microwave. However,many prior art container covers have suffered from deficiencies.Depending on their construction, they may be difficult to put on or toremove, or may be too easily detached, thereby resulting in inadvertentremoval of the cover. Many prior art container covers suffer fromdistortion when heated in the microwave. As a result, the attachment ofthe cover to the container is impaired or the quality of the sealbetween the cover and the container is reduced.

A need, therefore, exists for a cover that is easier to put onto andtake off of a container, inhibits inadvertent removal, and that sealsmore dependably.

SUMMARY OF THE INVENTION

The invention is directed to a container cover for use with a containerhaving a neck with an outer bead ring or lip. In exemplary embodiments,the container cover comprises a lid with a skirt extending downward fromthe circumference of the lid and a concentric plug seal extendingdownward from the bottom of the lid disposed inside the skirt. The skirtincludes a plurality of flexible lock panels each having at least oneinwardly projecting lock, which hold the cover in place on the containerby engaging the container neck bead ring. An edge of each lock panel isdefined by slots on either side that extend through the skirt and thatallow the lock panel to flex to disengage the bead ring.

When the cover is installed on the container, the locks on the inside ofthe lock panels engage the outside of the container neck, and the plugseal preferably sealingly engages the inside of the container neck. Inan embodiment, the lid is circular and fits on a container neck with acircular cross section. Also in a preferred embodiment, the skirtcomprises six flexible lock panels disposed around the circumference ofthe cover, defined by six vertical slots.

Other objects, aspects and advantages of the present invention willbecome apparent to those skilled in the art upon reading the followingdetailed description, when considered in conjunction with the appendedclaims and the accompanying drawings briefly described below.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of illustrating the invention, there are shown in thedrawings embodiments that are presently preferred; it being understood,however, that this invention is not limited to the precise arrangementsand constructions particularly shown. In the drawings:

FIG. 1 is a plan view of the top of an embodiment of a container coveraccording to the present invention.

FIG. 2 is a cross-section of the cover of FIG. 1 shown along lines 2-2.

FIG. 2A is an enlarged view of a portion of the cover shown in FIG. 2.

FIG. 2B is an enlarged view of the portion of the cover shown in FIG. 2with a second cover stacked on top.

FIG. 3 is a plan view of the bottom of the container cover of FIG. 1.

FIG. 4 is an isometric view of the container cover of FIG. 3illustrating the bottom of the cover.

FIG. 4A is an enlarged view of a portion of the cover of FIG. 4.

FIG. 5 is an isometric view of the top of the cover shown in FIG. 1.

FIG. 5A is an enlarged view of a portion of the cover of FIG. 5.

FIG. 6 is a cross-sectional view of the cover of FIG. 1, seen alonglines 2-2, and installed on a container, with a second container stackedon top.

FIG. 6A is an enlarged view of the cover and container stack shown inFIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings which illustrate several preferredembodiments of the invention, a container cover is shown for use on amicrowavable container. As will be discussed in more detail below, thecontainer cover preferably includes a plurality of integral lock panels.

The container may be of any size or shape and may be fabricated from anyof a variety of materials. Preferably, the container contains foodproducts which are heated in a microwave oven prior to consumption.Therefore, the container is preferably fabricated from a materialsuitable for use with food products and for heating in a microwave, forexample a thermoplastic material such as polypropylene formed byinjection molding. As shown in FIGS. 2A and 6A, the container 500preferably includes a neck or rim with a protruding lip having an outerbead ring 502, or similar structure proximate to its upper end 504. Theouter bead ring may be disposed directly adjacent to the upper end ofthe container or in close proximity thereto. While the container and thecover 10 are illustrated as each having a substantially circular shape,it will be appreciated by those of ordinary skill in the art that theteachings of the invention are applicable to a variety of other shapes.The following description and embodiments of the invention are notintended to describe all cover/container combinations, but are merelyillustrative of how the teachings of the present invention may beemployed in the context of a preferred container configuration.

The cover 10 is preferably microwavable and easily removed and reappliedto the container by the user. It is contemplated that the cover can belocked onto the top lip of the container during an assembly process atthe factory, keeping the top surface of the container clean duringshipping and storage. To remove the cover cap, the user can pull up onany one of the lock panels. This mechanical action moves the lock panelaway from a container bead ring 502, at least partially disengaging alock formed on the inside of the lock panel from the bead ring 502,thereby making it possible to lift a section of the cover 10. As theuser lifts up on one lock panel of the cover 10, the cover bends in arc.The connection through the skirt and lid of the adjacent lock panels tothe disengaged lock panel causes the adjacent lock panels to also flexaway from full engagement with the bead, thereby at least partiallydisengaging those lock panels from the container bead 502. Thus, thelifting of one lock panel results in at least partial disengagement ofthe cover 10 from the container 500, thereby allowing the user tocompletely disengage the cover 10 with relative ease.

In an exemplary implementation, after the user has removed the cover 10,the user opens the container, such as by pulling upward on a now exposedmetal ring tab of a sealed container top, completely separating the topfrom the container and discarding it. Next, the user replaces the coverand places the container and cover combination into a microwave oven.Vent holes may be included in the cover and serve to vent steamgenerated in the container by the heating process.

Referring to FIGS. 1, 2, and 3, the container cover 10 includes a lid20, having a top surface 21, a bottom surface 22, and a circumferentialedge 23. When installed on the container, the top of the lid faces awayfrom the container, and the bottom of the lid faces into the container.The cover also includes a skirt 30 extending downward from or near thecircumferential edge of the lid. The skirt has an inner surface 31 andan outer surface 32. When installed on the container, the outer surfacefaces away from the container, and the inner surface faces toward thecontainer and is preferably shaped to fit around the outside of thecontainer neck and/or outer bead ring. In a preferred embodiment, theskirt extends downward from the circumferential edge, preferably formingat least one stepped shoulder 34. Each shoulder is defined by asubstantially horizontal section extending radially outward from asubstantially vertical section of skirt, with the skirt continuing toextend substantially vertically downward from the horizontal section. Asshown in FIGS. 2B, 6, and 6A, the cover is designed to be stackable withcans or additional covers, which makes shipping and display moreconvenient. The skirt 30 preferably includes at least one, andpreferably two, shoulders 34 and 36 (shown more clearly in FIGS. 2 and2B), which have a larger diameter than, and are concentric with, thecircumferential edge 23 of the cover. The shoulders may be interruptedby bypass holes 90, located above the locks 70. The shoulders create atleast one space on which the base of a container or the skirt of asecond cover may rest when stacked, as seen in FIGS. 2B, 6, and 6A. Theshoulders also help to stiffen the connection between the skirt and thelid.

Preferably, a reinforcement bead 50 is molded around at least a portionof the bottom edge of the skirt and project radially outward from theskirt. The reinforcement bead 50 is visible in FIGS. 2B, 5, and 5A. Thisbead provides strength around the edge of the cover, stiffens the skirt,and prevents the cover from breaking when flexed during removal from thecontainer. It also helps the cover maintain its shape when heated, aswell as aiding the stacking of lids for transport or storage, as seen inFIG. 2B. Finally, the bead aids in removal by providing a greatersurface area for a user's fingers to act upon, thus reducing thepressure on the user's fingers.

The skirt 30 also preferably features scallops or recesses 35 on itslower edge. The scallops provide finger grips for the user and visuallyand tactilely indicate where the lid may be lifted around itscircumference. In a preferred embodiment, the scallops are includedaround the entire circumference of the skirt's bottom edge. Thecontainer cover is held onto the container by a plurality of locks 70and lock panels 40. The locks engage the outer bead ring on the neck ofthe container, as will be described hereinafter.

FIG. 4 is an isometric view of the bottom of the cover of FIG. 1. FIG.2A is an enlarged partial view of FIG. 2 (a cross-sectional view of FIG.1, seen along lines 2-2). Referring to FIGS. 2A and 4, a plug seal 60 ispreferably formed concentrically to the skirt 30 and has a smallerdiameter than the skirt. The plug seal extends from the bottom of thelid and preferably connects along its entire length to the bottom of thelid. As shown in FIG. 2A, the plug seal 60 has an outer surface shapedto preferably fit snugly and sealingly against the inside of the neck orrim of the container. Thus, the plug seal forms a seal against theinside surface of the container rim to prevent or inhibit the contentsof the container from readily passing between the container cover andthe container rim.

As shown in FIGS. 3 and 4, a plurality of stop ribs 65 preferably extendfrom the inside of the skirt and/or the bottom of the lid. The stop ribsare located so that, when the cover is installed on a container, thestop ribs touch the top of the container neck limiting the downwardmovement of the cover onto the container. As shown in FIGS. 2B and 4,stop ribs 65 preferably extend from the skirt and/or the lid, and do notinterfere with the plug seal when the cover is installed on a container.As shown in FIGS. 6 and 6A, the distance between the bottom of a stoprib 65 and the top of a lock 70 is preferably sized so that when thecover is installed on a container having a bead ring 502 on its neck,the bottom of the stop rib touches the top of the neck or the bead ring,and each lock engages the bottom of the container bead ring, therebylocking the container cover in place. The stop ribs preferably do nottouch the plug seal or cause seal distortions. This leaves the plug sealcompletely free from all connecting obstructions that create unwantedshrinkage, which can lead to leakage problems. Because the plug seal isuninterrupted, it is preferably completely round and provides a 360degree seal against the inside of the neck of the container.

FIGS. 2A and 4A illustrate the lock panel 40 in more detail. The lockpanel 40 is preferably formed as part of the skirt 30. The lock panelincludes at least one and optionally two locks 70 that extend radiallyinward from an inside surface of the lock panel 40. While only one lockis shown on each panel in FIG. 4, it is contemplated that each panel mayinclude a lock on each end of the panel. In a locked position, each lockpreferably engages the lower edge of the outer bead ring of thecontainer (especially upon lifting of the cover upwards.) In an unlockedposition, each lock is at least partially released from the outer beadring.

FIG. 4A is an enlarged view of a portion of FIG. 4 showing a lock panel40. Also shown is one of multiple slots 80, each of which are formed inthe skirt 30 on either side of a lock panel, thus defining the ends ofeach lock panel. The slots extend at least partially up the skirt.Preferably the slots extend at least halfway up the skirt between thebottom and top of the skirt. More preferably, the slots extend for morethan 50% of the skirt height. In a preferred embodiment, the slots areabout 0.06 inch wide and extend about 0.075 inch over the top of thelocks, although other slot sizes and placements can also be used.

Also, in a preferred embodiment (and as seen in FIG. 5), the scallopsformed in the lower edge of the skirt result in some slots beingslightly longer than others. Specifically, the slots alternate betweenbeing formed at the point where the scallop meets the bottom edge (thevertically lowermost point on the skirt and, thus, the longer slots) (80in FIG. 5), and at the base of a scallop (the vertically upward from theedge of the skirt and, thus, the short slots) (80′ in FIG. 5A).Preferably the locks are formed adjacent to the longer slots.

The slots permit the flexing of the lock panels 46, thereby permittingthe locks to disengage from the container bead. The flexible natureprovided to the lock panels by the slots makes the cover self-adjusting,and compensates for production variances in either the cover or thecontainer. In a preferred container/cover configuration, the containerhas a circular neck, and the cover has six slots equally spaced aboutthe skirt. The six slots form six approximately equally-sized lockpanels about the skirt. There is preferably one lock formed on the innersurface of each lock panel adjacent to a slot and, thus, the locks arepreferably on opposite sides of a slot. Thus in a preferred embodiment,three slots each have a pair of locks and three slots do not.

As discussed above, the locks 70 preferably extend radially inward fromthe inner surface of the skirt 30. A preferred form of the lock can beseen in FIGS. 2A and 4A, with a curved surface portion facing towardsthe top of the cover (i.e., upward), and a linearly sloping surfaceportion facing downward. When viewed from below, as in FIG. 3, the lockscan be seen to preferably feature a teardrop shape, although othershapes, such as semicircles, are contemplated. This shape creates atapered leading edge that aids in removal of the lid from the containerby providing an easier transition as the lid is flexing. While thepreferred embodiment includes a lock that features the illustratedcross-sectional shape, it is contemplated that other cross-sectionalshapes, such as triangles, flat-topped wedges, or circular shapes, maybe used.

Providing the slots through the skirt adds flexibility to the skirt andthe lock panels. Defining a lock panel by the slots allows the panel toflex outward away from the container rim as the locks pass over thecontainer bead ring when the cover is applied or removed. When removingthe cover, the slots in the skirt enable the lid to flex when the lockis lifted, promoting easy removal of the cover. The stiffness of eachlock panel may be adjusted by varying the length of the slots definingthe edge of the panel. It is contemplated that the slots adjacent to thelocks may extend through the top of the skirt; however, it is preferablethat the slots do not extend to the top of the skirt as the locks willlose some of their effectiveness, particularly during and aftermicrowaving.

The cover preferably has multiple open vent holes to automatically ventexcess steam and heat that could build up during the microwavingprocess. If the steam is not vented, the steam would build up within thecontainer and could potentially cause an injury to the user whenremoving the lid. In FIGS. 1, 3, 4, and 5, it can be seen that lid 20includes sloping transitional surface 100, which circumscribes a centralupper surface 110. A lower annular surface 120 circumscribes thetransitional surface 100. Vents or vent holes 130 are preferably formedin the container cover to allow air and steam to escape from thecontainer when the container's contents are heated. In the illustratedembodiment, the vents are formed on the sloping transition sectionbetween the lower annular surface and the upper surface. Thisconfiguration is designed to create a chimney effect whereupon the heatgenerated during cooking is channeled toward the center of the cover andescapes through the vents. This keeps the locks and plug seal cooler,and results in less potential for harm to the user while maintaining abetter seal. However, while this embodiment is preferred, other numbersor arrangements of vent holes may serve the same purpose. It should beapparent to one of ordinary skill in the art that while the embodimentfeatures a preferable number and arrangement of vent holes, any numberor arrangement of holes may serve substantially the same purpose.

The user may remove the cover by placing his finger tips under one ofthe lock panels and lifting upwards. The lifting action disengages thelocks that are molded on the inside surface of the lock panel. The slotsthrough the skirt assist in removal of the cover by allowing the entirelock panel to flex while being pulled out and away from the containerrim. When one lock panel is pulled upward, the adjacent panels begin toflex, causing the locks on those panels to disengage from the containerrim. Above each lock is preferably a bypass slot 90 that runs throughthe top and bottom surfaces of the lid. In one preferred embodiment, thebypass slot is formed during the molding process by dies that piercedownward through the lid. In one preferred embodiment, the die forces aportion of the lid material downward while in its moldable state to formthe lock. The illustrated embodiment in FIG. 5 shows a portion of theskirt above the lock as being “shaved,” which is the result of the dieforming the lock. Although the illustrated embodiment includes thebypass slots 90, it should be readily apparent that the openings are notnecessary in the cover. As shown in FIG. 5, this bypass slot follows thearc of the lid's circumferential edge and allows the lock panel to flexmore easily.

In a preferred embodiment, the locks are grouped in pairs, with threelock pairs spaced approximately every 120 degrees around thecircumference of the lid. This even spacing ensures uniform lockingpressure and minimizes distortion of the lid during heating. Theinclusion of multiple, evenly-spaced locks also allows removal of thelid by lifting the lid from any point around its circumference.Preferably, the ability to remove the lid by lifting at any point isindicated to a user by the inclusion of scallops forming finger recessesaround the entire circumference of the skirt.

Locating the locks on the skirt allows for simple assembly by placingthe cover over the container and pressing the cover directly down ontothe container. When the lock panels engage, they preferably make adistinct snap sound as the locks slide over the container bead. Thelocking action can also be felt by the user through the finger tips asthe locks lock over the container bead.

As previously described, the container cover is preferably made from onepiece of injection-molded polypropylene. Polypropylene has a tendency togrow slightly when heated in a microwave oven; such growth createsdimensional changes and deviations. Because the plug seal is in closestproximity to the heating container contents, it tends to experience morethermal growth than the rest of the cover components. The plug sealexpansion improves the seal between it and the container rim, thusserving to reduce the possibility of leakage when the contents areextremely hot. Because the locks are also in direct contact with thecontainer, positioning the locks adjacent to only some of the slots-thusspacing the locks farther apart—creates less vertical distortion of thecover components during heating.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the configuration of thepresent invention without departing from the spirit or scope of theinvention. It is intended that the present invention cover suchmodifications and variations provided they come within the scope of theappended claims or their equivalents.

1. A removable locking container cover for covering a container having aneck with an outer bead, the cover comprising: a lid having a topsurface, a bottom surface, and a circumferential edge; a skirt extendingdownward from the lid at or near the circumferential edge, the skirthaving a bottom edge, an inner surface and an outer surface, the innersurface shaped to extend around the outside of the container neck; and aplug seal extending from the bottom of the lid and concentric with theskirt, the plug seal having a smaller diameter than the skirt, the plugseal being connected to the bottom of the lid, the plug seal having aninner surface and an outer surface, the outer surface shaped tosubstantially be in contact with the inside of the neck of thecontainer; the skirt having a plurality of slots formed in the skirt andextending substantially vertically from the bottom edge of the skirt,the slots being spaced apart from one another around the skirt, eachpair of adjacent slots defining a lock panel thus forming a plurality oflock panels on the skirt, each lock panel having at least one lockformed on an inside surface of the lock panel and projecting inwardly,the lock adapted to engage a bottom edge of the outer bead of thecontainer when the cover is locked onto the container so as to removablyhold the cover in place on the container.
 2. The container of claim 1wherein the slots are substantially equally spaced around thecircumference of the skirt so as to form substantially equally sizedlock panels.
 3. The container cover of claim 1, wherein at least aportion of the bottom edge of each lock panel includes a scallopedcontour so as to define finger recesses.
 4. The container cover of claim1, wherein the lid further includes at least one hole extending throughthe lid so as to allow air to pass through the at least one hole.
 5. Thecontainer cover of claim 4, wherein the lid comprises a slopingtransition section between a lower annular surface and a central uppersurface, and wherein the at least one hole is a plurality of holesformed in the sloping transition surface.
 6. The container cover ofclaim 1, wherein the bottom edge of the skirt includes a molded beadprojecting radially outward from the skirt on each locking panel so asto provide an area of increased thickness.
 7. The container cover ofclaim 6, wherein the bead is continuous around the entire skirt andextends around the periphery of each slot.
 8. The container cover ofclaim 1, wherein each inwardly-projecting lock is located on the lockpanel adjacent to a slot.
 9. The container cover of claim 8, whereinthere slots have either a lock positioned adjacent to the slot or nolocks positioned adjacent to the slot.
 10. The container cover of claim1, wherein the lid further comprises a plurality of holes passingthrough the top and bottom surfaces of the lid, each hole locatedapproximately above a lock.
 11. The container cover of claim 1, furthercomprising a plurality of stop ribs connected to the inside of the skirtand to the bottom of the lid, the stop ribs disposed so that when all ofthe locks engage the container outer bead, substantially all the stopribs touch the top of the container neck so as to limit verticalmovement of the cover on the container.
 12. The container cover of claim1, wherein the skirt includes at least one shoulder extending radiallyoutward from, and concentric with, the circumferential edge of the lid,the skirt extending downward from the shoulder, the shoulder having adiameter larger than the circumferential edge, and configured to providea resting area for the bottom edge of the skirt of a second coverstacked on the cover.
 13. A removable locking container cover forcovering a container having a neck with an outer bead, the covercomprising: a lid having a top surface, a bottom surface, acircumferential edge, and a center section, the center section includinga lower annular section, a sloping transition section, an upper section,and a plurality of holes formed in the center section extending throughthe top and bottom surfaces so as to allow air to pass through the lid;a skirt extending downward from the lid at or near the circumferentialedge, the skirt having a bottom edge, an inner surface, and an outersurface, the inner surface shaped to extend around the outside of thecontainer neck; a plug seal extending from and formed integral with thebottom surface of the lid and concentric with the skirt, the plug sealhaving a smaller diameter than the skirt, the plug seal having an innersurface and an outer surface, the outer surface adapted to substantiallycontact the inside of the neck of the container; six integral lockpanels forming the skirt, each lock panel having at least one inwardlyprojecting lock formed on the inside surface of the skirt and configuredto engage a bottom edge of the outer bead of the container when thecover is locked onto the container so as to removably hold the cover inplace on the container, wherein the side of each lock panel is definedby a slot formed though the skirt, the slot extending substantiallyvertically from the bottom edge of the skirt, the slots positioned onthe skirt so that the at least one inwardly projecting lock is locatedbetween each set of slots.
 14. The cover of claim 13, wherein the locksare grouped in pairs, each pair adjacent to a slot such that one lock ofa pair is located on either side of the slot.
 15. The cover of claim 13,wherein at least a portion of the bottom edge of the skirt includes ascalloped contour so as to define finger recesses.
 16. The cover ofclaim 13, wherein the bottom edge of the skirt includes a molded beadprojecting radially outward from the skirt on each locking panel so asto provide an area of increased thickness for grasping by a user'sfingertips.
 17. The container cover of claim 16, wherein the bead iscontinuous around the entire skirt and extends around the periphery ofeach slot.
 18. The container cover of claim 13, further comprising aplurality of stop ribs connected to the inside of the skirt and to thebottom of the lid, the stop ribs disposed so that when the locks engagethe outer bead the stop ribs substantially touch the top of thecontainer neck, thereby limiting vertical movement of the cover on thecontainer.
 19. The container cover of claim 13, wherein the skirtfurther includes a shoulder projecting radially outward from, andsubstantially concentric with, the circumferential edge of the lid, theshoulder having a diameter that is larger than the diameter of thecircumferential edge, and which is configured to be concentric with thebottom edge of the skirt of a second cover when stacked on the cover.20. The container cover of claim 19, wherein the lid further includesthree bypass holes passing through the top and bottom surfaces of thelid, the bypass holes located on substantially the same diameter as theshoulder, each hole located approximately above a lock.